To explore normal and/or altered cellular functions which occur following carcinogen interactions with various cellular components, especially the significance of DNA interaction with carcinogens in the subsequent gene expression in active enzyme synthesis. To utilize the gene directed cell-free enzyme synthesis system to elucidate the mechanisms whereby these interactions affect cellular function; to examine the modifications in cellular function induced by carcinogens which lead to tumorigenesis; to develop means of controlling these altered cellular processes to either prevent or reverse carcinogenesis; and to develop systems which might rapidly and accurately predict carcinogenic potentials of chemicals.